Breaking Cosmological Parameter Degeneracies through Joint Analysis of Type Ia Supernovae, CMB, and BAO Observables
DOI:
https://doi.org/10.55544/jrasb.4.5.17Keywords:
Precision cosmology, Type Ia Supernovae, Cosmic Microwave Background, Baryon Acoustic Oscillations, Cosmological parameter degeneracy, ΛCDM model, Dark energyAbstract
Precise determination of cosmological parameters is fundamental to understanding the expansion history and large-scale structure of the Universe. Individual cosmological probes such as Type Ia Supernovae, the Cosmic Microwave Background (CMB), and Baryon Acoustic Oscillations (BAO) provide strong but degenerate constraints on key parameters when analyzed independently. In this study, we perform a joint likelihood analysis of SNeIa, CMB, and BAO observations to effectively break these parameter degeneracies and improve the precision of cosmological constraints. By combining late-time distance indicators with early-Universe and large-scale structure measurements, we obtain significantly tighter bounds on the Hubble constant, matter density, spatial curvature, and the dark energy equation-of-state parameter. The results are consistent with a spatially flat ΛCDM cosmology and indicate no significant deviation from a cosmological constant. This work highlights the power of multi-probe approaches in precision cosmology and underscores their importance for testing extensions to the standard cosmological model with current and future observational data.
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